From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Google-Smtp-Source: AB8JxZozNXgjucwaq1UrrCQ4vSZ2I2d+kiYL5iM8G4vhytmDUrDovjA12tWbZw1xdpMXcF/js006 ARC-Seal: i=1; a=rsa-sha256; t=1526937248; cv=none; d=google.com; s=arc-20160816; b=FozvMo/ISrh/pc2t4soNUA1+EL20FZW8KchWs+C45Kro5JzIs4G8u6e8FuoxPZS/+t bUAWUjCY9GP4vHkAdmsWGF1IxVB+kQxqOutkDvgYj5MT+nLzODKXU0950fP3DBnWEmMY CKRMYkV/J/UXsoJXdZUKIVtEP7hJIOrzuoSELlGrpU0rbTSe0oI4qop/G0UqgVC1Zdu2 t1Tv7soyzUdU2Tr7Ci502MkhU7MOvWWWEYNyAb+JF2yTBRGyYUeqB5cbjANBrMI9TMT5 vlzUx7vRue5hVBYJFzcUBj6OQGZ61BKdJ4pgsIHX/Ufpv9g/0G4s8//NtUKgC4dtRHco gYfQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=mime-version:user-agent:references:in-reply-to:message-id:date :subject:cc:to:from:dkim-signature:arc-authentication-results; bh=qzzHeMv0RpHgg3RurN4HaiO7FzqTyH8jlEewURgujNU=; b=K1M+lGKMvmrxIPL/7uWhwnq0dgl8SsbwIbMz/673qhfBKtwNMtuzUDNClv6TuNlnbl yaX24Xt+86n551v3UsznLa6mWoUU26P1DYsoz/ajzhrd3EnSGJ2lpfB2vffnuNzwu8EL qAowcL6C07XHPXdfmc6PcvH7ety11Ac0/DRhepAJ580IYWSPFwaklJMTWhnN90cjZsCf ns5MjEezFvItXl1T4aVX5TcbOXaphPrkiEjeRgAJVyeXko2y8TRtS+ABSoPDWFRgVADN zMwBx/VpO9qJwI1uRjKqibnWkQotosmO8y/TscOXeA6m9gzKvbWe5+KxExL8Ijah79Mu yJuQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=STah/RUm; spf=pass (google.com: domain of srs0=nia/=ii=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=nia/=II=linuxfoundation.org=gregkh@kernel.org Authentication-Results: mx.google.com; dkim=pass header.i=@kernel.org header.s=default header.b=STah/RUm; spf=pass (google.com: domain of srs0=nia/=ii=linuxfoundation.org=gregkh@kernel.org designates 198.145.29.99 as permitted sender) smtp.mailfrom=SRS0=nia/=II=linuxfoundation.org=gregkh@kernel.org From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Benjamin Herrenschmidt , Michael Ellerman , Michal Suchanek Subject: [PATCH 4.9 13/87] powerpc: Dont preempt_disable() in show_cpuinfo() Date: Mon, 21 May 2018 23:10:49 +0200 Message-Id: <20180521210421.462653316@linuxfoundation.org> X-Mailer: git-send-email 2.17.0 In-Reply-To: <20180521210420.222671977@linuxfoundation.org> References: <20180521210420.222671977@linuxfoundation.org> User-Agent: quilt/0.65 X-stable: review MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 X-getmail-retrieved-from-mailbox: INBOX X-GMAIL-LABELS: =?utf-8?b?IlxcU2VudCI=?= X-GMAIL-THRID: =?utf-8?q?1601109752390685238?= X-GMAIL-MSGID: =?utf-8?q?1601109752390685238?= X-Mailing-List: linux-kernel@vger.kernel.org List-ID: 4.9-stable review patch. If anyone has any objections, please let me know. ------------------ From: Benjamin Herrenschmidt commit 349524bc0da698ec77f2057cf4a4948eb6349265 upstream. This causes warnings from cpufreq mutex code. This is also rather unnecessary and ineffective. If we really want to prevent concurrent unplug, we could take the unplug read lock but I don't see this being critical. Fixes: cd77b5ce208c ("powerpc/powernv/cpufreq: Fix the frequency read by /proc/cpuinfo") Signed-off-by: Benjamin Herrenschmidt Signed-off-by: Michael Ellerman Acked-by: Michal Suchanek Signed-off-by: Greg Kroah-Hartman --- arch/powerpc/kernel/setup-common.c | 11 ----------- 1 file changed, 11 deletions(-) --- a/arch/powerpc/kernel/setup-common.c +++ b/arch/powerpc/kernel/setup-common.c @@ -228,14 +228,6 @@ static int show_cpuinfo(struct seq_file unsigned short maj; unsigned short min; - /* We only show online cpus: disable preempt (overzealous, I - * knew) to prevent cpu going down. */ - preempt_disable(); - if (!cpu_online(cpu_id)) { - preempt_enable(); - return 0; - } - #ifdef CONFIG_SMP pvr = per_cpu(cpu_pvr, cpu_id); #else @@ -340,9 +332,6 @@ static int show_cpuinfo(struct seq_file #ifdef CONFIG_SMP seq_printf(m, "\n"); #endif - - preempt_enable(); - /* If this is the last cpu, print the summary */ if (cpumask_next(cpu_id, cpu_online_mask) >= nr_cpu_ids) show_cpuinfo_summary(m);